Speed.docx

Calculative Methods or Formulas 1) Speed. Speed

⇒

Distance Time

Average Speed

Total DistanceCovered Total Time Taken

2) Velocity. Velocity

Distance Travelled ∈a Given Direction Time Taken

Velocity

Displacement Time Taken

Average Velocity Average Velocity

or

Distance Travelled Time Initial Velocity+ Final Velocity 2

( a=

u+ v ¿ 2

3) Acceleration. Acceleration

Change∈Velocity Time Taken for Change

Acceleration

Final Velocity−Initial v elocity Time Taken

Acceleration

Force Mass

( a=

F m

or ( a=

v−u t

)

)

4) Such Important Equations of Motion. v =u+at ❑

1 s=ut + at 2

2

v 2=u 2+ 2as

Where,

V= Final Velocity U=Initial Velocity S=Speed of Object A=Acceleration of Object T= Time

5) Uniform Circular Motion. V=

2 πr t

( v=Speed and t=Time )

6) Momentum. Momentum=Mass X Velocity ( P= mv ) Total Momentum Before Collision m1 u1 +m 2 u 2

=

=

Total Momentum After Collision

m1 v 1+ m2 v 2

7) Force. Force= Mass X Acceleration ( F= m x a )

8) Universal Law of Gravitational Motion. F=G

m1 m2 r

2

( G= 6.67 x

−11

10

N

2

−2

m kg

)

9) Acceleration due to Gravity. g =G

M R2

( g = 9.8m

−2

s

)

10) Equation of Motion for Freefalling Bodies. v =u ±> ¿❑ ¿ 1 2 h=ut ± > ¿ 2 ¿ 2

2

v =u ± 2 gh

11) Weight. Weight= Mass X Acceleration due to Gravity ( W= mg )

12) Pressure. Pressure =

Force Area

13) Density. Density =

Mass Volume

Relative Density =

Density of the Substeance Density of Water

14) Work. Work = Force x Distance ( W= F x S )

15) “Work Done Against Gravity” or “Potential Energy” Work Done in Lifting a Body = Weight of Body X Vertical Distance W= mgh Where, W= Work Done m = Mass of the Body g = Acceleration due to Gravity h = Height through Which the Body is Lifted

16) Formula for Work done When Body Moves at an Angle to the Direction of Force. W= F

cos θ

xS

Where, F= Force Applied

= Angle between the Direction of Force and Direction of Motion θ

S= Distance Travelled

17) Kinetic Energy. Kinetic Energy= Where,

1 2

m

v2

M = Mass of Body V = Velocity of Body or Speed of Body

18) Power. Power = Or

Work Done Time Taken

Power =

( P=

Energy Consume Time Taken

W t

) ( P=

E t

)

19) Sound. Speed of Sound = Frequency x Wavelength Speed of Sound x Time Distance Travelled by Sound = 2 Time Interval =

1 Frequency

Speed of Sound = Wavelength X Frequency

20) Time of Flight. “It is defined as the Total Time for Which the Projectile Remains in Air.”

T=

2 u sin θ g

21) Maximum Height. H=

u 2 sin2 θ 2g

22) Electric Current. Electric Current (I) =

Charge ( q) Time (t)

( I=

q t

)

23) Electric Potential. Electric Potential (V) =

Work Done(W ) Charge(q)

W q

( V=

)

24) Resistance. Resistance (R) =

Electric Potential(V ) Current ( I )

( R=

V I

)

25) Series Formula. Rp

=

R1

+

R2

+

R3

…….

( R= Resistance )

26) Parallel Formula. 1 Rp

1

1

= R + R + R ……. Electrical Heat. +1 1

Heat =

2

2

I Rt

3

( R= Resistance ) 27)

Where, I= Electric Current

R= Resistance T= Time

28) Electric Power. Power (P) = Electric Potential (V) x Current (I) Or, Power (P) = Power (P) =

Electric Potential (V )2 Resistance ( R)

Current ( I )2 x Resistance ( R )

(

( 2

P=I R

V2 P= R

(P=VI)

) or,

)

29) Electrical Energy. Electric Energy (E) = Power (P) x Time (t)

30) Mirror Formula. 1 1 1 + = v u f

Where,

F = Focal Length

( E= Pt )

U = Object Distance V = Image Distance

31) Linear Mirror Magnification. Mirror Magnification = Or,

m=

Height of Image Height of Object

−Image Distance Object Distance

=

hi −v = ho u

32) Lens Formula. 1 1 1 − = v u f

33) Linear lens Magnification. Mirror Magnification = Or,

m=

Height of Image Height of Object

=

Image Distance Object Distance

hi v = ho u

34) Refractive Index. Refractive Index( µ)=

Speed of Light ∈Vacuum/ Air c = Speed of Light ∈Given Medium n

35) Power of a lens. ( P=

1 ) f (¿ meter )

Power=

1 Focal Length (¿ meter )